[SierraWasp]

"But more importantly, they believe it has happened at least once before, and the results were nearly catastrophic to emerging cultures at the time."

Kinda reminds me of this data and model...

"In the six hundredth year of Noah's life, in the second month, the same day were all the fountains of the great deep broken up, and the windows of heaven were opened." Genesis 7:11

Something drastic happened then that changed the lifespans drastically and suddenly from Noah's 600+ years, down to Abraham's 120, or so. Something must have changed in the "firmament," also known as the "heavens" in those days... The timing would have been about 5200 years ago, as well!!!

[snarks_when_bored]

If you could suggest a mechanism whereby some sort of climate catastrophe caused human lifespans to shrink (virtually overnight, in geological terms) from 600+ years to 70+ years, I'd be interested in hearing it.